Specifications

Chapter 5. IBM System Networking RackSwitch implementation 171
Two trunk types are available:
򐂰 Static trunk groups (portchannel)
򐂰 Dynamic LACP trunk groups
Regarding the two RackSwitch types:
RackSwitch G8264 A RackSwitch G8264 switch supports up to 64 trunk groups (static and
LACP). Each type can contain up to 16 member ports.
RackSwitch G8124 A RackSwitch G8124 switch supports up to 24 trunk groups on the
switch (static and LACP). Each type can contain up to eight member
ports. Of the available configuration slots, any of them may be used for
LACP trunks, although only up to 12 may be used for static trunks. In
addition, although up to a total of 24 trunks may be configured and
enabled, only a maximum of 16 may be operational at any time.
For example, if you configure and enable 12 static trunks (the
maximum), up to four LACP trunks may also be configured and
enabled, for a total of 16 operational trunks. If more than 16 trunks are
enabled at any time, after the switch establishes the 16th trunk group,
any additional trunks are automatically placed in a non-operational
state. In this scenario, there is no administrative means to ensure
which 16 trunks are selected for operation.
The trunking feature operates according to specific configuration rules. When creating trunks,
consider the following rules that determine how a trunk group reacts in any network topology:
򐂰 All trunks must originate from one logical device, and lead to one logical destination
device. Usually, a trunk connects two physical devices together with multiple links.
However, in some networks, a single logical device may include multiple physical devices,
such as when switches are configured in a stack, or when using VLAGs. In such cases,
links in a trunk can connect to multiple physical devices because they act as one
logical device.
򐂰 Any physical switch port can belong to only one trunk group.
򐂰 Trunking from third-party devices must comply with Cisco EtherChannel technology.
򐂰 All ports in a trunk must have the same link configuration (speed, duplex, and flow
control), the same VLAN properties, and the same Spanning Tree Protocol, storm control,
and ACL configuration. The ports in a trunk should be members of the same VLAN.
򐂰 Each trunk inherits its port configuration (speed, flow control, and tagging) from the first
member port. As additional ports are added to the trunk, their settings must be changed to
match the trunk configuration.
򐂰 When a port leaves a trunk, its configuration parameters are retained.
򐂰 You cannot configure a trunk member as a monitor port in a port-mirroring configuration.
򐂰 Trunks cannot be monitored by a monitor port; however, trunk members can
be monitored.
Static trunks
By default, each trunk group is empty and disabled. To define a static trunk group, complete
the configuration steps in this section.
Static trunks: Static trunks are configured in the reference architecture on the links
between AGG-1 and AGG-2, AGG-1 and ACC-1, AGG-1 and ACC-2, AGG-2 and ACC-1,
and AGG-2 and ACC-2.